Uniform distribution of TiO2 nanocrystals on reduced graphene oxide sheets by the chelating ligands

Reduced graphene oxide–TiO2 hybrids were successfully prepared by the hydrothermal approach using triethanolamine and acetylacetone as the chelating agents. Without any additive, large aggregated TiO2 clusters were randomly distributed dominantly at the edge and less on the basil plane of coagulated reduced graphene oxide (RGO) layers. The presence of chelating ligands remarkably facilitated the selective growth and regular spread of TiO2 nanocrystals onto individually exfoliated RGO sheet. Such sandwich-like structure with stronger coupling and chemical interaction resulted in the surface area increase, the rearrangement of energy level, the enhanced concentration of oxygen vacancies, leading to much higher adsorbability and photocatalytic degradation of Rhodamine B under both UV and visible irradiations. These RGO–TiO2 hybrid systems are potentially beneficial for widely practical applications in air/water purification, electronic devices, batteries, solar cells or supercapacitors.